Adaptive head and neck restraint system for a vehicle occupant

ABSTRACT

Head and neck restraint apparatus for an occupant of a vehicle comprises a stiff yoke shaped to engage the upper torso and shoulders of the occupant. The yoke is generally U-shaped, with a base and upwardly extending limbs, and has a frontal portion shaped to extend over the chest of the occupant which corresponds to the base of the U. An intermediate portion of the yoke is shaped to fit over the shoulders of the occupant, and an upper portion of the yoke, corresponding to the upper ends of the limbs, extends beyond the intermediate portion to constrain movement of a helmet worn by the occupant. A set of first guides on the yoke are arranged to engage harness members of a safety harness worn by the occupant. Each guide is shaped to engage a respective harness strap or buckle and responds to longitudinal movement of the harness strap or buckle. Tensioning members connected between the respective guides and the helmet apply a tensioning force to the helmet when movement of the occupant causes displacement of the harness relative to the yoke. A set of second guides that respond to lateral movement of the harness is also provided.

BACKGROUND OF THE INVENTION

THIS invention relates to a head and neck restraint system for anoccupant of a vehicle.

The occupant of a vehicle such as a high performance motor racingvehicle, a high speed power boat or the like is subjected to significantaccelerations, particularly in the event of a crash. Occupants of suchvehicles generally wear a crash helmet and a four- or six-point harnesssecuring them in position in a seat.

Various systems have been proposed for enhancing the protection offeredto the occupant of such a vehicle by tethering the occupant's helmet toa support structure of some kind. For example, it has been proposed toprovide a yoke which rests on the upper torso of the occupant, to whichthe helmet is tethered. The purpose of such devices is to limit themovement of the helmet and hence the head and neck of the occupantrelative to the occupant's torso when substantial accelerations areexperienced, particularly in a crash.

It is an object of the invention to provide alternative head and neckrestraint apparatus.

SUMMARY OF THE INVENTION

According to the invention there is provided head and neck restraintapparatus for an occupant of a vehicle, the apparatus comprising:

-   -   a stiff yoke shaped to engage the upper torso and shoulders of        the occupant, the yoke having a frontal portion shaped to extend        over the chest of the occupant, an intermediate portion shaped        to fit over the shoulders of the occupant, and an upper, helmet        engaging portion extending beyond the intermediate portion and        shaped to constrain movement of a helmet worn by the occupant;    -   a plurality of first guide means associated with the yoke and        arranged to engage harness members of a safety harness worn by        the occupant, each guide means being shaped to engage a        respective harness member and being responsive to longitudinal        movement of said harness member relative to said guide means;        and    -   a plurality of tensioning members connectable between the        respective guide means and the helmet,        so that movement of the occupant causing displacement of the        harness relative to the yoke results in a tensioning force being        applied to the helmet by at least one tensioning member.

The yoke is preferably generally U-shaped, with a base and upwardlyextending limbs, the base of the U corresponding to the frontal portionof the yoke and the upper ends of the limbs corresponding to the helmetengaging portion thereof.

A pair of first guide means are preferably mounted on the frontalportion of the yoke, each guide means being arranged to receive arespective strap of a safety harness worn by the occupant.

Preferably, each first guide means is shaped to engage a buckle or otherformation on the strap so that longitudinal movement of the straprelative to the first guide means, at least in one direction, isprevented.

Preferably each first guide means is mounted slidably relative to theyoke so that an acceleration causing movement of the occupant and theyoke relative to the harness causes sliding displacement of the firstguide means relative to the yoke.

The tensioning members are preferably flexible cords fixed to the firstguide means at one end thereof and connectable to respective fixingpoints on the helmet in use.

Preferably, the yoke defines a guide for each tensioning member toensure correct orientation thereof in use.

For example, the yoke may define conduits extending between a lower edgeof the frontal portion of the yoke, adjacent to the first guide means,and respective inner surfaces of the helmet engaging portion of theyoke.

Preferably, the apparatus includes a plurality of second guide meansmounted on the intermediate portion of the yoke and arranged to engagerespective harness members passing over the shoulders of the occupant inuse, the second guide means being responsive to lateral movement of theharness members due to movement of the occupant causing displacement ofthe harness relative to the yoke, with a plurality of tension memberseach connectable between a second guide means and the helmet.

Each second guide means is preferably mounted slidably relative to theyoke so that an acceleration causing lateral movement of the occupantand the yoke relative to the harness causes sliding displacement of thesecond guide means relative to the yoke.

The head and neck restraint apparatus is thus operable to constrainmovement of the occupant's helmet, and thus the occupant's head andneck, relative to the occupant's torso as a result of movement of theoccupant in both fore-and-aft and lateral directions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial view of head and neck restraint apparatusaccording to the invention;

FIG. 2 is a pictorial view similar to that of FIG. 1, showing the rangeof movement of first and second guide means of the apparatus;

FIG. 3 is a pictorial view similar to those of FIGS. 1 and 2, showingthe straps of a harness engaged with the apparatus;

FIG. 4 is a similar illustration to that of FIG. 3, additionally showinga helmet of a user of the apparatus in position adjacent to theapparatus;

FIGS. 5 & 6 are side views showing the apparatus in use, before andafter an impact;

FIG. 7 is a front view of a user of the apparatus, corresponding to FIG.5;

FIG. 8 is a similar view to that of FIG. 7, showing the effect of alateral impact on the user; and

FIG. 9 is a top view of the user, corresponding to FIG. 6.

DESCRIPTION OF EMBODIMENTS

FIGS. 1 and 2 show an embodiment of head and neck restraint apparatusaccording to the present invention. The apparatus is intended for use byoccupants of vehicles, boats, aircraft and other craft or vessels thatmay be subject to rapid accelerations or impact in use. For purposes ofthis specification, the word “vehicle” is intended to refer to any andall vehicles, crafts, conveyances or the like.

The apparatus comprises a yoke 10 which is generally U-shaped and whichhas a frontal portion 12 corresponding to the base of the U, anintermediate portion comprising a pair of limbs 14 and 16 whichgenerally correspond to the limbs of the U, and a pair of upper, helmetengaging portions 18 and 20 which correspond to the upper ends of the U.

The yoke 10 is preferably rigid and can be molded from a suitably strongplastics material, glass fibre and resin, or a light weight compositematerial comprising carbon fibre or Kevlar (trade mark), for example. Itwill be appreciated that the materials indicated are merely exemplaryand that other suitable materials could also be used.

The yoke is shaped to rest of the shoulders of a user of the apparatus,with the frontal portion of the yoke lying over the upper torso or chestarea of the user. The limbs 14 and 16 include curved shoulder engagingformations 22 and 24 which extend over and behind the shoulders of theuser in use, locating the yoke firmly on the upper torso of the user.When so located, the yoke defines an opening 26 below and around theneck and head of the user. The opening 26 is sized to permit a degree ofunimpeded movement of the user's neck relative to the yoke, but thewidth is less than the width of a conventional crash helmet worn by theuser, preventing the yoke from being lifted upwardly off the user whilethe user is wearing the helmet.

The upstanding helmet engaging members 18 and 20 have curved innersurfaces 28 and 30 shaped complementally to the curvature of a typicalcrash helmet, allowing them to extend close to the crash helmet in usewithout impeding its movement unduly as the user moves his or her head.Thus, the user can rotate his or her head from side to side whilewearing the yoke 10. The helmet restraining members 18 and 20 limitrearward movement of the helmet relative to the yoke, but permit freeforward movement of the helmet.

Mounted on the body of the yoke are two pairs of guides which engage thestraps of a four- or six-point harness worn by the user. A first pair ofguides 32 and 34 are mounted on the frontal portion of the yoke, on itsupper surface and towards opposed side edges thereof. A second pair ofguides 36 and 38 are mounted on respective upper surfaces of theshoulder engaging portions 22 and 24 of the yoke.

The guides 32 and 34 each comprise a generally cruciform bracket havinga pair of arms 40 and 42 extending on either side of an elongate centralmember 44. Outer ends 50 and 52 of the arms 40 and 42 are curvedinwardly, enabling them to retain a harness strap between them in use.An elongate slot 46 extends substantially the entire length of thecentral member 44 and is sized to fit about the shaft of a bolt 48 fixedto the yoke so that the entire guide can slide longitudinally relativeto the bolt, between the positions shown in solid and dotted outlines inFIG. 2.

The guides 36 and 38 are simpler in design, each comprising an elongatemember 54 having a longitudinally extending slot 56 therein. A bolt 60retains each guide 36, 38 slidably on the yoke, allowing it to movebetween the positions shown in solid and dotted outline in FIG. 2. Theelongate member 54 has an inwardly curved outer end 58 at an outer endof the member 54, for retaining a harness strap in the guide.

At the lowermost ends of the guides 32 and 34, and at the innermost endsof the guides 36 and 38, attachment points 62 are provided to which arefixed respective flexible cords 64 and 66. The attachment points eachdefine one or more holes or slots through which the cords 64 and 66 arethreaded and looped to lock them in a desired position on the guides.For example, in the case of a user with a relatively long neck, thecords will be adjusted to be longer than for a user with a shorter neck.

The cords 64 attached to the guides 32 and 34 pass through respectiveopenings 68 in the front edge of the frontal portion of the yoke 10 andthrough conduits or passages 70 defined in the body of the yoke, exitingat respective openings 72 in the helmet engaging surfaces 28 and 30. Thecords 66 pass through respective conduits 74 and out of the sameapertures 72. The exit points for the cords defined by the apertures 72are generally at least 115 mm below and 125 mm behind the centre ofgravity of the head of an average user of the apparatus seated in anupright neutral position.

The cords 64 and 66 serve as tensioning members or tethers which arefixed to attachment points on the rear side surfaces of the user'shelmet in use. The cords will normally be attached to an FIA certifiedhelmet mount or existing helmet strap which is located below andgenerally behind the centre of gravity of the user's head. The cordswill typically be a Kevlar or Vectran (trade marks) fibrous cord, orcomprise a similar suitable material, which is flexible butnon-extendable under tension.

When a user is wearing the yoke and a helmet, as shown in FIG. 4, thecords 64 and 66 are attached to a helmet 76 as shown, with justsufficient play to allow normal movement of the user's head withoutpulling the cords tight.

Referring now specifically to FIGS. 3 and 4, the interaction between theapparatus of the invention and a safety harness worn by the user of theapparatus is shown.

The user wears a four-, five- or six-point harness including a pair ofstraps 78 and 80, which pass over the shoulders of the user torespective anchorages 82 in the vehicle at the upper end of the backrest84 of a seat occupied by the user. Such a harness always has shoulderportions and lap portions and, in five- and six-point harnesses, alsohas one or two crotch portions. Thus, a four-point harness will compriseleft and right shoulder portions and left and right lap portions makingup the four points, with five- and six-point harnesses having one or twoadditional crotch portions, respectively.

Conventionally, such harnesses have adjustable buckles which allow thestraps 78 and 80 to be adjusted snugly over the user's shoulders. In theillustrated prototype apparatus of the invention, these buckles 86 arereceived by the guides 32 and 34, with the straps 78 and 80 beinglocated and retained by the inwardly curved outer ends of the arms ofthe guides. The upper edge of the buckle abuts the ends of the arms,preventing the buckle from moving longitudinally past the guide. Thestraps also pass through the guides 36 and 48 as shown in FIG. 4, beingretained in position on the guides by the curved outer ends thereof.

Instead of providing guides that engage existing buckles on the harnessstraps, it is also possible to provide strap engaging means in the formof clamps or gripping members which are fastened to the strap at adesired location. The rollers are arranged to wind the tether cordsaround a reel or shaft when an impact causes the harness straps to moverelative to the yoke and rotate the rollers. In such an embodiment, theharness strap will slide over the roller and the friction between theroller and harness strap will cause the roller to rotate and so wind thecord onto it, tensioning the cord.

In another embodiment, rollers can be mounted on the upper guides 36 and38 in an integrated system in which the rollers react to longitudinalmovement of the harness and lateral sliding of the guides takes place inresponse to lateral movement of the harness.

In the event of an impact, the torso of the user moves relative to theharness straps, typically by as much as 100 mm. The movement of the userrelative to the harness in the case of a frontal impact is shown inFIGS. 6 and 9. The user's torso is displaced relative to the strapsthemselves, and consequently relative to the position of the harnessbuckles or other strap engaging means. The yoke 10 moves forward withthe user's torso in this scenario, causing the strap buckles to slideupwardly, together with the respective guides 32 and 34, relative to theyoke. This pulls the cords 64 tight, exerting a pre-tensioning force inthe direction of the arrow in FIG. 6. This force maintains the correctorientation of the helmet 76 and prevents the user's head from extendingforwards.

As best indicated in FIGS. 7 and 8, when a lateral impact occurs, theuser's torso is displaced laterally relative to the initial position ofthe harness straps, causing an outward displacement of one or the otherof the guides 36 or 38 and tensioning the respective cord 66, thusexerting a corrective pre-tensioning force on the user's helmet andmaintaining the correct alignment of the user's head and neck.

1.-11. (canceled)
 12. Head and neck restraint apparatus for an occupantof a vehicle, the apparatus comprising: a stiff yoke shaped to engagethe upper torso and shoulders of the occupant, the yoke having a frontalportion shaped to extend over the chest of the occupant, an intermediateportion shaped to fit over the shoulders of the occupant, and an upper,helmet engaging portion extending beyond the intermediate portion andshaped to constrain movement of a helmet worn by the occupant; aplurality of guide means associated with the yoke and arranged to engageharness members of a safety harness worn by the occupant, each guidemeans being shaped to engage a respective harness member and beingresponsive to movement of said harness member relative to said guidemeans; and tensioning members connectable between the respective guidemeans and the helmet, so that movement of the occupant causingdisplacement of the harness relative to the yoke results in a tensioningforce being applied to the helmet by at least one tensioning member. 13.The apparatus of claim 12, wherein the yoke is generally U-shaped, witha base and upwardly extending limbs, the base of the U corresponding tothe frontal portion of the yoke and the upper ends of the limbscorresponding to the helmet engaging portion thereof.
 14. The apparatusof claim 12, wherein said plurality of guide means comprises: a pair ofguide means mounted on the frontal portion of the yoke, each said pairof guide means being arranged to receive a respective strap of a safetyharness worn by the occupant.
 15. The apparatus of claim 14, whereineach of said pair of guide means is shaped to engage a formation on thestrap so that longitudinal movement of the strap relative to said guidemeans, at least in one direction, is prevented.
 16. The apparatus ofclaim 12, wherein each of said plurality of guide means is mountedslidably relative to the yoke so that an acceleration causing movementof the occupant and the yoke relative to the harness causes slidingdisplacement of said guide means relative to the yoke.
 17. The apparatusof claim 12, wherein said tensioning members are flexible cords fixed tosaid guide means at one end thereof and connectable to respective fixingpoints on the helmet in use.
 18. The apparatus of claim 12, wherein theyoke defines a guide for each tensioning member to ensure correctorientation thereof in use.
 19. The apparatus of claim 18, wherein theyoke defines a plurality of conduits extending between a lower edge ofthe frontal portion of the yoke, adjacent to said guide means, andrespective inner surfaces of the helmet engaging portion of the yoke.20. The apparatus of claim 12, wherein said guide means is mounted onthe intermediate portion of the yoke and arranged to engage respectiveharness members passing over the shoulders of the occupant in use, saidguide means being responsive to movement of the harness members due tomovement of the occupant causing displacement of the harness relative tothe yoke, with a plurality of tension members each connectable betweensaid guide means and the helmet.
 21. The apparatus of claim 20, whereinsaid guide means is mounted slidably relative to the yoke so that anacceleration causing lateral movement of the occupant and the yokerelative to the harness causes sliding displacement of said guide meansrelative to the yoke.
 22. The apparatus of claim 20, wherein the yokedefines a plurality of conduits extending between the intermediateportion of the yoke, and respective inner surfaces of the helmetengaging portion of the yoke.